Composite integral sliding mode control for PMSM

Based on the mathematical model and state equation of the permanent magnet synchronous motor (PMSM), a composite nonlinear integral sliding surface which contains integer order integral and fractional order integral was proposed, and the corresponding sliding mode controller was designed in order to improve the dynamic performance and robustness of the PMSM position control system. For further improving the robustness to load disturbance and eliminate the system chattering, the fractional order integral to the sliding surface was considered as a feedforward compensation in the control output. The stability of the proposed method was proved by the Lyapunov stability theory. The simulation results show the dynamic performance and robustness of the proposed method.